Modern societies have developed various processes to transform energy into useful work driven by various types of fuels. For example, gasoline may be ignited to drive pistons that deliver torque to the wheels of a car. Fossil fuels, for example, coal, may be consumed in large quantities in many electric power plants that distribute electric power over large transmission networks. Other fuel sources may be used to generate useful mechanical, electrical, or other type of work.
A class of fuels that may be new to fossil fuels may be referred to as a biofuel. Biofuel may be generally understood as including a type of fuel that is generated from biomass. Biomass may generally be considered biological matter from living or recently living organisms that can serve as an energy source. Examples of biomass may sometimes include waste, wood, gas, and alcohol. Concern over increasing oil prices, energy security, greenhouse gas emissions from fossil fuels, and government subsidies has garnered increased interest in biofuels.